Black Spring — Christina Henry

A former Agent of death, Madeline Black now has everything to live for, most importantly, her unborn child. But Chicago has become ground zero in a struggle between ancient creatures, and only Maddy can stop the carnage…

The mayor of Chicago has announced a plan to round up the city's supernatural beings and put them in camps. With her due date looming, Maddy's best move would be to lay low for a while. But not everyone is willing to respect her privacy. Hounded by tentacled monsters, a rogue shapeshifter, and a tenacious blogger, Maddy turns to her most powerful ally, her uncle Daharan, only to find him missing.

Just when it seems like things can't get any worse, Maddy gets an invitation in the mail -- to Lucifer's wedding. Turns out everyone has been invited, friends and enemies alike. And with that kind of guest list, it's highly unlikely there will be a happily ever after.